In the course of machining workpieces, it is necessary to simultaneously lubricate the workpiece and pass a cooling medium over it to transfer heat generated during a machining operation. It has been found that an oil-water emulsion serves to accomplish the optimum.
Unfortunately, in some instances other fluid mediums used by the machine, e.g., gear-box lubricants, hydraulic fluids, mix with the oil-water emulsion, causing a breakdown of the oil-water emulsion. The result has been that the workpiece and machine tool have not been properly lubricated and cooled. More specifically, it has been found, for example, that a source of the contaminating fluid has been hydraulic fluid adapted for use with a machine, e.g., hydraulic means for moving the machine into and out of an operative position relative to a workpiece. It has been found that fluid escapes from the machine due to a number of reasons, e.g., seal leakage, overflow from hydraulic oil supply tanks. What occurs is that the hydraulic fluid drips onto the floor where it flows to a collecting trough. The trough is the same trough which collects oil-water emulsion which drops to the floor or is otherwise directed to the collecting trough. The excess hydraulic fluid, often referred to as "tramp" fluid, mixes with and contaminates the emulsion and causes an undesirable breakdown of the oil and water in the oil-water emulsion supply tank. More than a minor amount of tramp oil in the oil-water emulsion renders the emulsion unstable and necessitates shutting down the machining operation until the contaminated fluid is removed from the system. It can be readily appreciated that shutting down the machining operation can be quite costly.
What is desired is a system adapted for use with trough collecting stations presently employed for collecting overflow fluids whereby the second fluid is collected and are prevented from contaminating the main supply tank of first fluid.